Automatic telephone system.



. r. mm sfi uuzmwfi M I. :0 i m l o :2 s a m .M u n n A M b 8 W M H W v m A m a. m W a I S. B. WILLIAMS, In. AUTOMATIC TELEPHONE SYSTEM. APPLICATION FILED JAN I4 1915 S. B. WILLIAMS, In. AUTOMATIC TfLEPHONE SYSTEM. 7 I APPLICATION FILED JAN. 14. I916. I 1,237,,433. I I Patented Aug. 21, 1917.

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//7V/7/0/.' Jamaal 15. MW/k/WJJK w Amk UNITED STATES PATENT OFFICE.

SAMUEL B. WfLLIAMS, J3, OF BEOQKLYN,

NEW roux. assmuoa to warm "up onto oomramr, INOORBORATED, on NEW 101m, 21-. 1., AOORPOMIIOH or m AUTOMATIC TELEPHONE SYSTEM.

Patented Aug. 21, 1917.

1 Application filed Jlnuary'll, 1918. Serial No. 72,136.

To all whom it may concern Be it known that I SAMUEL B. Wrpnmzas, J r., a citizen of the nited States, residing at Brooklyn, in thecounty of kings and State of New York, have invented certain new and useful Improvements in Automatic Telephone Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to telephone s s terns, in which the talking connection e tween subscribersdines is established wholly or in part by means of electrically actuated switching devices.

The principal feature of the invention resides in the provision of means for controlling the operation of such electrically actu ated switching devices over the third or nontalking conductor of the connecting circuits aratus, backover employed.

)ther features, which result from or are incident to the main object above noted, will appear during the description of the invention. i ,Fignresyl and 2, with Fig. 1 at the left, diagrammatically indicate the apparatus and the circuits employed in carrying out this invention. At the left in Fig. 1, a line finder switch is diagrammatically indicatod for connecting the calling line 1 with the trunk circuit 2. This means ofwouneoting the line to the trunk, however, forms no part of the present invention, and could be accomplished as well by a line or trunk-find ing switch, or even by a manual switch as a plug and jack, as the invention is equally applicable to, telephone systems in which the mcchanicalswitches are controlled by a central office operator as to full automatic 'sys tems.

Assuming now that the brushes 3, 4 and 5 of-the finder switch are positioned on the contacts of the line 1, and that the:side

switch wipers 6, 7 and 8 have moved to position 4, a circuit-will extend from battery, through the right winding of impulse relay 1), wipers 7',b rush 4, over the left side of the subscribers line, through the substation aptheright side of the line, rush '5, wiper 8 y and back to battery,

througlithe-left wim'lini, of relay 9. Relay.

9' attracts its armature, and completes a circuit 'for the slow-release relay [0.

The calling subecribernow opemtes her,

. relay 9 retracts its armatures, but relay 10 being slow to act, holds up over these interruptious. it may be here noted that if this invention is employed in a semi-automatic telephone system, the impulse relay will not be connected .to the talking conductors but will be controlled by the operators sending device. lVith the first retraction of the armature of relay 9, a circuit is'completed from battery through'the rotary-stepping magnet 11 and the escape magnet relay 12 in parallel, and thence through wiper 13. A circuit is also' completed from battery, through the release relay 1.4, to the wiper 13, the circuits being continued to ground through the front contact and armature of relay 10,"and the back contactand armature of relay 9. Magnetll and relays 12 and 14: will be energized. Relay 14 will now be held up over a circuit extending through both front contacts and the armature of relay 10 to ground through resistance 15. This resistance 15, however, is so high'asnot to hold up the armature of.1nag|ict .11 or rc-- moved from one group of connecting cir-' -c|lit contacts to the next.

Any stcp-by-step, two-movement switch may heemploye'd with the circuits shown, A switch of this general character issliown in. patent to Keith anddlrickson No. 815,17t'u However, in the-descriptionof the presentinvention thesteiping magnet whicl'i'ii-rst o Joratcs ls descrl ed as the l'otar magnet.

'l hat in an around-and-u switci instead of the up-and-aroruu'l switch shown 'in-"tlie Keith at al. patent, is assumed to he ployed in the present circuits.' A switch of this character .is' shown in an application of Oscar l Forshe|-g,.Serial No. 6,302, filed February 6, t 1916.; The; sido switch cmployed in the present invention may be of the type shown in the Keith ct al. patent, or ot"the type similar to that disclosed in the F'orsberg"application.

Resinning now the description of the operation of the circuits, when the last impulse is sent, relay 0 will remain energized,

holdilug open theeircuit' for the slow-re-- lease relay 12 and for the rotary magnet 11. The switch brushes will he stopped in operative relation, on in the present instance, justbelow. the group of trunk contacts desired. When the relay 12 attracted its armature, it completed a circuit for the escape magnet 10' which now retracts'its armature and moves the side switch wipers to position In position .2 a circuit is completed t'rom hatter)"through the test relay 20, side switch wipcr- 1'1. and the normally closed contact 22. Contact 22 opens .on the first rertical step. The test-relay in attractingits armature, completes a circuitv for the escape magnet 10'.- circuit is also completed from battery. through the vertical stepping nmgnct- 23. oil-nornnil contact 24, \\l|)0l' -25 and interrupter 20 to ground. The circuit of the vertical stcpping magnet willbe alternately opened and closed by the interrupter 2o. causing the sclector brushes 10.117. 15 to more from trunk to trunk of the selected group. The lower or .test contact of all busy trunlgs. will be connected to ground.tlnfo u'ghresistance Iii.

liy'a circuit extending through the .ln'ush 1S and side switch \\'ipe|'s.21 and 1 of the selector. switchesassociated with said busy trunks. Thus the test relay .20 will be held energized iintil the contacts of an idle trunk are engaged. The test contact of such a trunk will not be connected to ground and relay 20 .will retract its armature opening the circuit for the escape. magnet 10'. which in turn retracts its armature and mores 'the side. switch to posit-ion 1. The vertical olfnormal contact LZ-l is closed during the upward movement of the switch. and opens on the-tenth i'crtical step, in order. to prevent jamming of theswitch in case -no idletruuk present systheselector switclrof lig. l were the hundreds impulses. the,suhscriberl would now o )erate=.-l |is d'ial to seinl din. tens impulses, causing arsenic-sot interruptions in the aircuitof relay 5). as, before. With the first retraetiona-ot the arn atnr'en -E relay it, circuits will be. completed from battery through energized. thus stopping the switch brushes if desired however other change and L thatt.lie .scr|cs of impulses which operatedrelease relay 101. the rotary stepping magnet; 102 and the escape relay 1.03. The circuit for the rotary magpet 102 passes through side switch wi er 104, where it joins the lead from 1tela 103. The circuit is then extended through the left armature and back contact of relay 105 to the lead from relay 101: the circuit being continued through brush Its. wipers .21 and 13. front contact of relay 10 and the back contact of relay 0. Magnet 102 and relays 101 and 103 are all energized. Relay 101 will be held up by the path to ground through resistance if). in the same manner as relay 11. Relay 103 being slow to release its armature, remains up during the series of impulses. The armature of the'rotary step- .ping magnet 10'. is alternately attract-ed and minati.on of the series of impulses, the rotary stepping magnet 102 will remain dein operative relation to the tens group of contacts in which the wanted line terminates. 'hen the armature of relay 103 wasattracted. it completed a circuit from battery through the escape magnet 100, and the alternate contact and armature of relay 10:1. to ground. causing the energization of the escape magnet. I'pon the termination of the series of impulses. relay 103 will retract. its armature. opening the circuit for the escape magnet 10!) and permitting the side switch to more to position 2.

The calling subscriber will now send the last or units series of impulses. With the first dceuergization of the relay 9. the Vet tical. magnet 110 and rela 103 will be energized iu'a'lnanncr similar to that described in connection with rotary magnet 10;! and relay [0%, upon sending the tens series of impulses. 'lhc brushes of the. connector switch will now he stepped from line to line of the desired groups'nntil they are positioncd'on the contacts of the wanted subscriber's line.

i be connected to battery-only through its cut-elf relay. 11; andlmttery. \Vhen relay. 103 was energized. due to sending the units series of impulses. the escape magnet 109 was energized in the same manner as before. Now. upon the retraction of the ar- '1natu| 'e of' relay 103. at the end' of'the unit series (rim'pulses: a' circuit is completed :from hattelfy. through the winding of mag-' 'net'109', the tnornnrl Contacts of relay 103,

105 and its right normal contact,

test rela 108 to the .test termiwi er 1'11and brush na of the called line.

As before stated, if the called line is busy,

one of its multiple test terminals will be connected to ground. and test relay 105 will be energized, and in' attracting its armature, will. con'iplete a locking circuit for itself and magl'iet 100, through its right alternate contacts and the side switch wiper 121. The .magnet 109 being now energized, and the side switch being in position 2, the busy tone'device'llfi will be connected to the talk ing circuit through the left armatureand front contact of escape magnet 109 and side switch wiper 114.

It will he noted that the busy tone device was connected to the upper conductor of the talking circuit, durin the sending of the last series of impulsesfbut as the calling subscribefis receiver is short-circuited by contacts of'the sending device during the transmission of the impulses, and the side switch. would be moved to position 3 simul- I taneously with the opening of the short-circuiting contacts at the sender, he would not hear the buzz if the wanted line was idle.

However, assuming that the line is and that the subscriber hears'the buzz, and replaces his receiver on the hook, relay 9 will be deenergized and will interrupt and hold open the circuit for relay 10 which will retract its armature, thus opening the holding circuit for the release relay 14 of the selectorswitch, and the release relay 101 ofv the connector switch. Relay'14 inretracting its battery through the release magnet 537, rotary off-normal contact 28, closed on the first rotary step, and the armature and back con tact of relay 14 to ground, thus causing the. restoration of the selector switch. Relay 101, in. retracting .its armature, completes a circuit from battery, through release relay 115, rotary off-normal contact 116, closed on the first rotary step, the armature and back contact of relay 101, thus causing the restoration of the connector switch. It will be noted that the holding circuit, through the. escape magnet 109 and the test relay 105, is maintained until the switch is released and the side switch brushes are returned to-nm ma], thus preventing ringing on busy lines.

Assuming now that the wanted line is idle, its test contact will not be COI'lIlBCtGd to ground. 'lhus relay 105 will not be ener gized and the escape magnet 100 will retractits armature,moving the side switchto position 3. In position 3 a circuit is closed from battery through the escape magnet 100, the arn'iature and coritact of trip relay 117 and ,sideswitchwiper 121 to ground. The escape magnet 109 attracts its armatures and completes a circuit from the generator 118, atbroi' h trip relay 117, the right armature busy armature, completes a circuit from and contact of the escape magnet 109, side switch wiper 119, brush. 107, over the right side of the subscribers line, through the bell of the wanted subscribers substation set, back'over the left side of the line, brush 100 and side switch wipers 120 and 121 to ground. This will cause the operation of the bell of the wanted subscriber. The busy tone device will not be connected to the talking conductor at this time, as the side switch is in osition 3. y r I pon the closing of the called'subscrili)e|"s hook switch, the increased fiow of current through the trip relay 117 will cause it to attract its armature, thus interrupting the circuit for the escape magnet 109 and :ausing the side switch to move to position 4., in which position the talking circuit will be established from the callin to the called line. Talking current is supplied to the calling subscriber through the windings o the impulse relay 9 and td the called subscriberthrough resistances and Busy potential will be supplied to the test contact of the called line 111 in positions 3 and 4. a

By the present invention, atelephone system is provided in which the switches, used in establishing a connection are controlled solely over the third or non-talking conductors of the connecting circuit. That is, the impulses for setting up the connection are transmitted over the third or test conductor, and the release of the switches is controlled over this same conductor, thus avoiding the necessity of associating any operatingmagnets or relays with the portion of the talking circuit extending to the called subscriber which is physically disconnected from the portion connected to the calling subscriber.

What is claimed is:

1. In an automatic exchange system, subscribers lines, means including a. selector switch for establishing a.connection from one 01 said lines to another, a connecting circuit extending to said selector switch, said com'iecting circuit including a non-talking conductor, a stepping magnet for said selector switch connected directly to said.

non-talking conductor, and means for transmitting impulses over said conductor to operate said stepping magnet.

2. In an automatic exchange system, subscribers lines,,means including a selector switch for establishing a connection from one of said lines to another, a connecting circuit extending to said selector switch,

said connecting circuit including a nontalking conductor, a stepping magnet for said selector switch connected directly to said non-talking conductor, means for transmitting impulses over said conductor to operate said stepping magnet, a release magnet for said selector switch, and means for conthrough side switch wiper trolling said release magnet over said nontalking conductor.

3. ln an'automatic exchange system, subscribers 'liues, means including a selector 5 switch for establishing a connection from .one of said lines to another, a connecting circuit extending to said selector switch, said connecting circuit including a non-talking conductor, a stepping magnet for said selector switch,

relay for controlling said ielease ma net said stepping magnet and said release rela being connected in parallel to said non-talking conductor, means for transmitting impulses over said stepping magnet, and'means for controlling said release relay over said conductor.

4. In a telephone exchange system, a plurality of lines, means including electricallyoperated switches and connecting circuits for establishing connection between said lines, said connecting cilcuits each comprising a pair of talking conductors and a nontalking conductor, an impulse relay, :1 stepping magnet associated with each connecting conductor to operate said f circuit connected directly to ing conductor, and means for impulse relay to operate said nets successively said switches in said non-talkoperating said stepping mag to cause the operation of establishing a connection.

In a telephone exchange systen1,,aeallmg subscribers line and a called subscri rs lme, means including a series of electrically operated switches and connecting 'cic'uits for establishing a connection from said calling line to said called line, said connecting circuits including a non-talking conductor, a stepping magnet and a release magnet for each of said switches,

ductor, means for transmitting impulses over said conductor to operate said stepping magnets, and means for controlling said release relays over said conductor.

ln witness whereof, I hereunto subscribe any name this 13th day of January, A. D.

SAMUEL B VILLIAMS, JR. 

